Copolymerization Arrhenius plot

Dilution with toluene slowed the copolymerization rate, and kinetic measurements were carried out in toluene at 0°-30°C. As reported previously (II), the over-all activation energy of the spontaneous copolymerization of CPT and S02 was calculated to be 16.5 kcal/mole from the Arrhenius plot of the initial rate vs. polymerization temperature. Dependence of the intial rate of copolymerization upon monomer concentration was checked at various monomer concentrations and found to be quite high (II) this could not be explained without participation of the monomer in the initiation step. 

An Arrhenius plot of the copolymerization is shown in Figure 4. The result indicates that the polymerization mechanism is different between the higher-temperature and lower-temperature region. An activation energy of —0.8 kcal/mole was obtained for the region below — 9°C. Above — 9°C, the activation energy is about 2 kcal/mole. 

Figure 4. Arrhenius plot of the copolymerization of ethylene-hexafluoroacetone...

Figure 22-12. Arrhenius plot for the temperature dependence of the copolymerization parameters in the free radical copolymerization of styrene (S) with acrylonitrile (AN).

Considering cyclopentene as representative of the cyclic olefins, the kinetics of its copolymerization with MA was investigated.The copolymerization rate data showed a maximum rate at approximately 40 mol % MA. An Arrhenius plot of the rate data and interpretation of the results yielded an overall activation energy of 24.2 0.35 kcal/mol. No thermal initiation was detected for the C4-C8 olefin-MA copolymerizations. 

Aromatics, MA acylated, 91-98 /3-Aroylacrylic acids, synthesis and use, 92-98 Arrhenius equation, preexponential factors, 508 Arrhenius parameters, MA production, 32 Arrhenius plots, MA copolymerization, 310, 320, 324, 331, 350, 361, 386, 406 Aryldiazonium chlorides diethyl fumarate adduct, 221 dimethyl fumarate adduct, 221 dimethyl maleate adduct, 221 MA adduct, 221... 

Fig. 1. Arrhenius plot (least squares fit) of the literature terminal reactivity ratio data for SAN copolymerization versus temperature...

Figure 21 Arrhenius plots of ethene and acrylate reactivity ratios and Ta, respectively, for copolymerization of the binary systems E-MA (triangles), E-BA (squares), and E-EHA (circles) at 2000bar. The dashed lines represent the fit to the combined data set for E-BA and E-EHA. Erom Buback, M. Drdge, T. van Herk, A. Mahling, E.-O. Macromol. Chem. Phys. 1996, 197, 4119. ...

From the logarithmic plot of the Arrhenius equation shown in Figs. 8 and 9, the overall activation energy, / p, was calculated to be 0.65 and 0.56 Kcal/mol for AM-AANa and AM-DAEA-HCl systems, respectively. However, the corresponding reported values for gamma radiation induced copolymerization of acrylamide with DMAEM-MC in aqueous solution was found to be 2.0 Kcal/mol [16]. 

In Figure 7 the r values are plotted according to the Arrhenius equation. The temperature dependence of the r values does not agree with the Arrhenius equation. Therefore, one of the basic assumptions underlaying Equation 37 is false. To explain the experimental copolymerization data, the condition of an equilibrium constant independent of the a-methylstyrene sequence length is best considered. 

The temperature dependence of the copolymerization rates were examined over the range 40-90°C. The results were plotted using the Arrhenius equation to give the activation energies Er shown in Table 10.3. 

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